Snow provides an unexpected opportunity for some tourists to unleash their artistic talent on the Bund in Shanghai on Tuesday. [China Daily]

"The extreme low in the suburbs could still be down to minus 1 to 3 degrees Celsius, where ice could reoccur," she added.

The weather yesterday brought the cleanest air to the city since the adoption of a new, more stringent air evaluation system in mid-November.

Tiny PM2.5 particulates, the city's major pollutant in winter, remained below 30 micrograms per cubic meter during the entire day yesterday. In the early morning, the figure was less than 10.

The reading of the fine particles started to rise at 9am and reached a peak of 28 micrograms per cubic meter at 3pm.

At 5pm, the reading was 16.8 micrograms per cubic meter and its density in the latest 24 hours was 14.1 micrograms per cubic meter, far lower than the national limit of 75 micrograms per cubic meter.